Anatomy

Muscles are bundles of fibers that contract and expand, which causes movement. When these muscles are regularly stretched and conditioned, their bundles of fibers lengthen, allowing them to contract and tighten more vigorously during exercise. Muscles that are poorly conditioned are more susceptible to fatigue, which can alter spinal neural reflex activity. When muscles are tired, their oxygen supply is depleted, leading to the buildup of waste products and spasms. When a cramp begins, the spinal cord stimulates the muscle to keep contracting.

About

A muscle spasm, also known as a muscle cramp or “charley horse,” is an involuntary contraction of a muscle that occurs suddenly and does not relax. Although knee muscle spasms can happen to any muscle, the most commonly affected muscle groups are:

  • Back of the lower leg/calf
  • Back of the thigh
  • Front of the thigh
  • Feet, hands, and arms
  • Abdomen and ribcage

The exact cause of muscle spasms is unknown. Factors such as poor stretching and conditioning, muscle fatigue, exercising or working in intense heat, dehydration, and depletion of salt and electrolytes contribute to muscle spasms.

Those who are at the highest risk of getting muscle spasms include infants, young children, and people over the age of 65. Other factors that can put people at a greater risk for muscle spasms include:

  • Certain medications
  • Being overweight
  • Illness
  • Overexerting during work or exercise

Muscle spasms are most common among athletes – specifically endurance athletes like marathon runners.

Causes

Spams might result from several underlying causes, including:

  • Tense muscles
  • Poorly conditioned muscles
  • Heat exhaustion
  • Dehydration
  • Nerve damage
  • Limited blood supply
  • Significant or chronic physical, mental, or emotional stress
  • Overuse

In some instances, spasms that cannot be traced back to any specific cause or no known reason and are called idiopathic muscle spasms.

Athletic woman on running track has muscle spasm and touching hurt leg

About knee muscle spasms

Knee muscle spasms range in intensity and can be mild to extremely painful. Sudden and intense pain is usually the benchmark symptom of a muscle spasm. This discomfort often is a burning, stretching, or tearing sensation. The pain typically lingers for anywhere from several seconds to hours. Additionally, the stricken muscle might twitch and feel hard and tender to the touch. When experiencing a muscle spasm, the muscle may appear visibly distorted. These spasms can last from a few minutes to a few hours and may reoccur many times before they go away.

Diagnosis

Although most muscle cramps are non-threatening, sometimes they can indicate a serious medical condition. See your Florida Orthopaedic Institute physician if your cramps are severe, happen frequently, respond poorly to simple treatments, or are not related to obvious causes like strenuous exercise. It is possible that you may have problems with circulation, metabolism, hormones, nerves, nutrition, or medications.

Muscle spasms can be a symptom of many conditions that range from minor to severe, such as spinal nerve irritation or compression, thyroid disease, narrowing of the spinal canal, hardening of the arteries, chronic infections, cirrhosis of the liver, and Lou Gehrig’s disease.

Your Florida Orthopaedic Institute physician will check all other symptoms you may have, decide what your exact condition is, and create a treatment plan based on the results of your diagnosis.

It is important to remember that spasms usually result from a specific underlying problem, so doctors must identify that issue before creating any type of treatment plan. In many instances, diagnosing a muscle spasm is a multi-step process beginning with questions about your medical history, such as:

  • What actions bring forth the spasms?
  • When did the problem start?
  • Do any movements worsen the pain?
  • How long has the problem been taking place?
  • Do any other symptoms accompany spasms?
  • Have you been diagnosed with any health conditions?
  • Your diet?
  • What leisure activities do you participate in?

Doctors might also ask about your stress levels, your fitness, and your sleeping patterns. After gathering this information, your doctor will likely perform a visual exam of the afflicted muscle or muscles, looking out for any apparent abnormalities suggesting possible injury. They may also perform various tests to identify medical problems capable of causing muscle spasms, like dehydration, nutritional deficiencies, or low electrolyte levels.

Treatment

The therapy your doctor chooses will depend on the underlying cause.

The best treatment for a sudden (acute) event is time. Most muscle spasms do not last for prolonged periods. When one happens, you may be able to ease your discomfort through immediate efforts such as:

  • Stretching the ailing muscle
  • Massaging the aching physical feature
  • Moving or walking around
  • Using over-the-counter pain-relieving medications only as directed and for a brief time frame

You might also lessen your pain by applying ice and heat alternately.

Home treatments

Muscle spasms usually go away on their own without having to see a doctor. But when a muscle spasm occurs, you should:

  • Stop whatever activity triggered the cramp
  • Gently stretch and massage the muscle, holding it in a stretched position until the cramp goes away
  • Apply heat to tight/tense muscles

When to see a doctor

You should seek medical attention if spams cause severe discomfort or limit your ability to perform routine tasks, are accompanied by swelling or skin rashes, create noticeable muscle weakness, occur with increasing frequency, or do not improve after using self-care methods.

Prevention

It may be difficult to prevent muscle spasms. You may be able to lower their risk by:

  • Drinking adequate amounts of water
  • Consuming a nutritious and balanced diet
  • Obtaining enough exercise
  • Preparing muscles for physical activity through stretching and loosening exercises
  • Getting enough sleep
  • Participating in productive stress-busting activities

Other possible preventative measures include adequately fitting footwear, maintaining a healthy weight, and, whenever possible, not working out or performing any other strenuous tasks in warm weather.

Cover of Everything You Need to Know About Muscle Spasms

Learn everything you need to know about muscle spasms in our downloadable guide.

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